As a result of the ever-increasing demand for broadband communications involving voice, video and data transmission, telecommunication and cable media service providers and/or operators have increasingly relied on fiber optics to provide large bandwidth telecommunication service to their subscribers. Fiber optic solutions have become the main part of telecommunication networks. Optical cables can transmit voice, data and video signals over very long distances at very high speed. Because of this, developments in fiber optic telecommunication networks have consistently focused on extending the optical fiber closer to the subscriber to the point that currently the subscriber can be connected directly to the fiber optic network through FTTx (fiber to the specific location “x”) technology, including FTTH technology (fiber-to-the-home), which provides an “all optical” communication network right to the subscribers at their homes. This deployment of optical fiber toward the subscriber is being driven by ever-increasing demand for more bandwidth, whether the optical fiber reaches all the way to the subscriber or not.
However, the subscriber's home may not be a separate, free-standing house, but an apartment building, referred to as a multiple dwelling unit (MDU). The apartment buildings may be very old and were built during a time when no one ever dreamed of broadband communications, fiber optic networks, or the internet. In addition, construction techniques, materials and building codes may have been significantly different from what they are today. Moreover, there are different kinds of MDUs, each kind requiring different types of complicated cabling systems to retrofit a fiber optic network in the MDU. Typically, separate cables are used with each cable connected to one subscriber. Installation of many cables which provide the connection between a main distribution point (which usually is located in the basement or in another place of the building) and the subscriber may cause significant and numerous problems with routing through the wall or levels of the building, in addition to mounting and installing fiber optic equipment. As a result, such installations consume a lot of time and costs, particularly with regard to retrofitting such a network in existing buildings having current tenants.
Referring to FIG. 1, there is shown a conventional fiber optic network 100 installed in a typical MDU. The MDU 110 has multiple floors or distribution levels 112, four of which are shown in FIG. 1. Each floor 112 is provided optical service by a riser cable 114 extending vertically from a lower floor 112, which may be a basement (not shown in FIG. 1). The riser cable 114 has spaced apart access points 116 which may be set at the factory. In FIG. 1, the access points 116 have been set to align with each floor 112, but the access points 116 may be set for any appropriate spacing, for example, every other floor 112 based on the number of subscribers per floor 112 or to accommodate the architectural structure of the MDU 110.
The access point 116 may be a FlexNAP™ system provided by Corning Optical Communications LLC of Hickory, N.C. At the access point 116 one or more optical fibers of the riser cable 114 separate or are tapped off from the riser cable 114 by a tether cable 118 which routes to a distribution box 120 located at the particular floor 112. The distribution box 120 may be a fiber distribution terminal (FDT) or may be a local convergence point (LCP). In the case of an FDT, the tether cable 118 may be a multi-fiber cable and the distribution box 120 may be used to interconnect each optical fiber in the tether cable 118 to an optical fiber in a subscriber drop cable 122, which routes to a subscriber premises 124 to provide optical communication service to that particular subscriber. In such case, the distribution box 120 will have a patch panel to make such interconnections. Alternatively, the distribution box 120 may include an optical splitter 126 and function as an LCP. Instead of the optical fiber in the tether cable 118 being directly connected to an optical fiber in the subscriber drop cable 122, the optical fiber is connected to the optical splitter 126 which splits the optical signal in the optical fiber into multiple optical signals. Each of the split optical signals is carried by a separate optical fiber and interconnects with an optical fiber in the subscriber drop cable 122 routed to the subscriber premises 124.
An LCP is shown in the break-out detail in FIG. 1. Referring to the detail, the tether cable 118 separates from the riser cable 114 at the access point 116 and extends toward the optical splitter 126. It should be noted that, although the riser cable 114 and the access point 116 are shown being routed within the distribution box 120, the riser cable 114 and the access point 116 may be positioned outside of the distribution box 120, and, may even be located outside of the MDU 110 and be exposed to environmental elements. The optical splitter 126 and input terminal blocks 128 may be positioned in a separate section or sub-enclosure 130 of the distribution box 120. The tether cable 118 may enter the sub-enclosure 130 through a port or be connected into the sub-enclosure by a suitable fiber optic connector 132. An optical fiber 134 from the tether cable 118 connects to the optical splitter 126 through input terminal blocks 128 by way of input optical fiber 136. The optical splitter 126 splits the optical signal carried by the input optical fiber 136 into multiple optical signals. In the detail for FIG. 1, the optical splitter 126 splits the optical fiber into four optical signals each of which is carried by a separate output optical fiber 138. The output optical fibers 138 route to output terminal blocks 140 and interconnect to the output fibers 142. Each output 142 may be included in a subscriber drop cable 122 with individual subscriber drop cables 122 bundled together into a bundled drop cable 144 using a helical wrap. The bundled drop cable 144 and, therefore, the subscriber drop cables 122 connect to the distribution box 120 through a multi-fiber connector 146 and extend to the subscriber premises 124. A drop box 148 at the subscriber premises 124 receives the bundled drop cable 144 and one of the subscriber drop cables 122 separates from the bundled drop cable 144 and routes to the subscriber premises 124.
Whether the distribution box 120 is a FDT or a LCP, sufficient space on the floor 112 is required for mounting and installing the distribution box 120, and for connecting the tether cable 118 and the subscriber drop cable 122 to the distribution box 120. This requirement becomes costly, not only with respect to the material necessary for each floor 112, but also, for the labor involved with such installation. This is particularly applicable in the event the fiber optic network is being retrofitted into an existing MDU, and increasingly problematic the older the MDU.
Consequently, there is an unresolved need for devices that provide better options for optical fiber deployments.
No admission is made that any reference cited herein constitutes prior art. Applicant expressly reserves the right to challenge the accuracy and pertinence of any cited documents.